1. Field of the Invention
This invention relates generally to reducing the loss and/or damage caused by an earthquake, in particular, to artificially triggering a catastrophic earthquake to happen at a known time without having to rely on imminent earthquake prediction so that pre-earthquake evacuation and preparation can be implemented prior to the known time.
2. Description of the Related Art
Catastrophic earthquakes occur almost every year in the world, causing tremendous loss and damage. Most catastrophic earthquakes are tectonic earthquakes that are caused by sudden releasing of underground elastic strain energy accumulated over time. People have been trying to develop techniques to predict the earthquakes, so that mitigation actions can be taken prior to the earthquake. Earthquake predictions may be roughly divided into four types: long-term predictions which are made in units of several tens of years; intermediate-term predictions made in units of several years; short-term predictions aiming at predicting an earthquake from several months to several tens of days before the occurrence; and imminent predictions aiming at predicting an earthquake from several days to several hours before the occurrence. While long-term predictions and intermediate-term prediction technologies have been making progress by researchers, effective pre-earthquake mitigation actions usually still have to rely on imminent earthquake predictions or at least short-term predictions. Unfortunately, due to the complexity of the nature of the tectonic earthquakes, many catastrophic earthquakes do not have any foreshocks or other indicators before occurring, imminent and short-term earthquake predictions have extremely low successful rate and many seismologists believe it is technically impossible in the foreseeable future.
Therefore, there is a need in the art to work-around the technical difficulties of imminent and/or short-term earthquake predictions to effectively enable evacuation and other pre-earthquake mitigation actions.